In the July 2005 issue (“What is the best way to distinguish type 1 and 2 diabetes,” J Fam Pract 2005; 54:630–633), Vincent Lo asserts in his clinical commentary that “distinguishing between type 1 and type 2 diabetes is neither clinically helpful nor cost effective.” In their recent Position Statement, the American Diabetes Association states that labeling the type of diabetes is less important than knowing the pathogenesis of the hyperglycemia.1 We think we may lose this knowledge of pathogenesis if we never attempt to identify patients who do not produce endogenous insulin.
As an example from our practice, a 60-year-old obese woman with coronary artery disease was admitted with diabetic ketoacidosis. Her C-peptide was undetectable. On subsequent hospital admissions, it is essential that her exogenous insulin be continued to prevent iatrogenic diabetic ketoacidosis, and this information must be conveyed to the team caring for this patient. A patient who does not produce endogenous insulin needs to have basal insulin replacement at all times to prevent iatrogenic diabetic ketoacidosis.2 In these patients, management with only an insulin sliding scale can have severe complications.
While the assertion that distinguishing between type 1 and 2 diabetes may be correct in most outpatient situations, in the inpatient setting managing patients who do not produce endogenous insulin is often quite different from managing those who do.
Jeanne P. Spencer, MD,
and Stephanie Miller, PharmD
Conemaugh Memorial Medical Center
Family Medicine Residency Program
Johnstown, Pa
REFERENCES
- American Diabetes Association: Diagnosis and classification of diabetes mellitus (Position Statement). Diabetes Care 2005; 28(Suppl 1):S37-S42.
- Clement S. Braithwaite SS, Magee MF, et al. Management of diabetes and hyperglycemia in hospitals. Diabetes Care 2004; 27:553-591.
Dr Lo responds:
The comments of Dr. Spencer and Dr. Miller were appreciated. While knowing the pathogenesis of the hyperglcemia is important, checking insulin C-peptide remains not always helpful and cost-effective.
In the example of a 60-year-old obese woman admitted with diabetic ketoacidosis, it was clinically obvious that the patient would require exogenous insulin replacement therapy. It is often a misguided practice for physicians to use sliding scale insulin coverage to address hyperglycemia in hospitalized patients. Sliding scale insulin is often not adequate and appropriate for long-term management of patients with diabetes who are insulin-dependent.
I agreed that it is critical to address the need for basal insulin requirement for both hospitalized and outpatient patients who required exogenous insulin replacement.
Vincent Lo, MD
St. Elizabeth Family Medicine Residency, Utica, NY;
SUNY Upstate Medical University, New York